//#include <bits/stdc++.h>
using namespace std;

#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define RFOR(i, a, b) for(int i = (a) - 1; i >= (b); i--)
#define SZ(a) int(a.size())
#define ALL(a) a.begin(), a.end()
#define PB push_back
#define MP make_pair
#define F first
#define S second

typedef long long LL;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef double db;

const int INF = 1e9 + 47;

int f(const set<int>& s, int h)
{
	auto it = s.lower_bound(h);
	int res = INF;
	if (it != s.end())
		res = min(res, *it - h);
	if (it != s.begin())
		res = min(res, h - *prev(it));
	return res;
}

struct SegTree
{
	int n;
	vector<set<int>> t;
	void init(int _n)
	{
		n = 1;
		while (n < _n)
			n *= 2;
		t.clear();
		t.resize(2 * n - 1);
	}
	void upd(int v, int tl, int tr, int pos, int h)
	{
		t[v].insert(h);
		if (tl == tr - 1)
		{
			return;
		}
		int tm = (tl + tr) / 2;
		upd(2 * v + 1, tl, tm, pos, h);
		upd(2 * v + 2, tm, tr, pos, h);
	}
	int query(int v, int tl, int tr, int l, int r, int h)
	{
		if (r <= tl || tr <= l)
			return INF;
		if (l <= tl && tr <= r)
			return f(t[v], h);
		int tm = (tl + tr) / 2;
		return min(query(2 * v + 1, tl, tm, l, r, h), query(2 * v + 2, tm, tr, l, r, h));
	}
} st;

void solve()
{
	int n, m;
	cin >> n >> m;
	st.init(n);
	while (m--)
	{
		int t;
		cin >> t;
		if (t == 0)
		{
			int x, h;
			cin >> x >> h;
			x--;
			st.upd(0, 0, st.n, x, h);
		}
		else
		{
			int l, r, h;
			cin >> l >> r >> h;
			l--;
			int ans = st.query(0, 0, st.n, l, r, h);
			cout << (ans == INF ? -1 : ans) << "\n";
		}
	}
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	int t;
	cin >> t;
	while (t--)
	{
		solve();
	}
	return 0;
}

answer.code:14:9: error: ‘vector’ does not name a type
   14 | typedef vector<int> VI;
      |         ^~~~~~
answer.code:15:9: error: ‘pair’ does not name a type
   15 | typedef pair<int, int> PII;
      |         ^~~~
answer.code:20:13: error: ‘set’ does not name a type
   20 | int f(const set<int>& s, int h)
      |             ^~~
answer.code:20:16: error: expected ‘,’ or ‘...’ before ‘<’ token
   20 | int f(const set<int>& s, int h)
      |                ^
answer.code: In function ‘int f(int)’:
answer.code:22:19: error: ‘s’ was not declared in this scope
   22 |         auto it = s.lower_bound(h);
      |                   ^
answer.code:22:33: error: ‘h’ was not declared in this scope
   22 |         auto it = s.lower_bound(h);
      |                                 ^
answer.code:25:23: error: ‘min’ was not declared in this scope
   25 |                 res = min(res, *it - h);
      |                       ^~~
answer.code:27:37: error: ‘prev’ was not declared in this scope
   27 |                 res = min(res, h - *prev(it));
      |                                     ^~~~
answer.code:1:1: note: ‘std::prev’ is defined in header ‘<iterator>’; did you forget to ‘#include <iterator>’?
  +++ |+#include <iterator>
    1 | //#include <bits/stdc++.h>
answer.code:27:23: error: ‘min’ was not declared in this scope
   27 |                 res = min(res, h - *prev(it));
      |                       ^~~
answer.code: At global scope:
answer.code:34:16: error: ‘set’ was not declared in this scope
   34 |         vector<set<int>> t;
      |                ^~~
answer.code:1:1: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
  +++ |+#include <set>
    1 | //#include <bits/stdc++.h>
answer.code:34:16: error: ‘set’ was not declared in this scope
   34 |         vector<set<int>> t;
      |                ^~~
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:16: error: ‘set’ was not declared in this scope
answer.code:34:16: note: ‘std::set’ is defined in header ‘<set>’; did you forget to ‘#include <set>’?
answer.code:34:9: error: ‘vector’ does not name a type
   34 |         vector<set<int>> t;
      |         ^~~~~~
answer.code: In member function ‘void SegTree::init(int)’:
answer.code:40:17: error: ‘t’ was not declared in this scope
   40 |                 t.clear();
      |                 ^
answer.code: In member function ‘void SegTree::upd(int, int, int, int, int)’:
answer.code:45:17: error: ‘t’ was not declared in this scope
   45 |                 t[v].insert(h);
      |                 ^
answer.code: In member function ‘int SegTree::query(int, int, int, int, int, int)’:
answer.code:59:34: error: ‘t’ was not declared in this scope
   59 |                         return f(t[v], h);
      |                                  ^
answer.code:61:24: error: ‘min’ was not declared in this scope
   61 |                 return min(query(2 * v + 1, tl, tm, l, r, h), query(2 * v + 2, tm, tr, l, r, h));
      |                        ^~~
answer.code: In function ‘void solve()’:
answer.code:68:9: error: ‘cin’ was not declared in this scope
   68 |         cin >> n >> m;
      |         ^~~
answer.code:1:1: note: ‘std::cin’ is defined in header ‘<iostream>’; did you forget to ‘#include <iostream>’?
  +++ |+#include <iostream>
    1 | //#include <bits/stdc++.h>
answer.code:87:25: error: ‘cout’ was not declared in this scope
   87 |                         cout << (ans == INF ? -1 : ans) << "\n";
      |                         ^~~~
answer.code:87:25: note: ‘std::cout’ is defined in header ‘<iostream>’; did you forget to ‘#include <iostream>’?
answer.code: In function ‘int main()’:
answer.code:94:9: error: ‘ios’ has not been declared
   94 |         ios::sync_with_stdio(0);
      |         ^~~
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